鼠李糖乳杆菌抑制阪崎克罗诺杆菌致脑膜炎的体内外实验

Lactobacillus rhamnosus GG inhibits Cronobacter-induced meningitis in neonatal rats

目的考察鼠李糖乳杆菌(LGG)对阪崎克罗诺杆菌致脑膜炎的抑制作用。方法以Caco-2细胞为体外模型,采用黏附侵袭实验研究阪崎克罗诺杆菌对Caco-2细胞的黏附侵袭作用及最佳感染时间,并用不同浓度的LGG与Caco-2细胞作用,确定其抑制阪崎克罗诺杆菌的最佳浓度。进一步通过竞争、排斥和置换实验检测LGG对阪崎克罗诺杆菌黏附侵袭的抑制作用。通过体内实验,研究LGG对乳鼠脑膜炎的作用效果。结果阪崎克罗诺杆菌对Caco-2细胞具有黏附侵袭性,最佳感染时间为3 h。随着加入LGG浓度的增加,阪崎克罗诺杆菌对Caco-2细胞的黏附和侵袭作用被显著抑制。LGG能通过竞争、排斥作用抑制阪崎克罗诺杆菌对Caco-2细胞的黏附。LGG对阪崎克罗诺杆菌引起的脑膜炎具有预防和治疗作用,且预防效果更显著。结论通过体内外实验,LGG可以抑制阪崎克罗诺杆菌进入肠屏障,从而减少其穿越血脑屏障的量,最终达到预防和治疗脑膜炎的效果。

Objective To investigate the inhibitory effect of Lactobacillus rhamnosus GG （LGG） against Cronobacter-induced meningitis in neonatal rats. Methods The cell adhesion and invasion capacities of Cronobacter were assayed in Caco-2 cells, and the optimal time length and concentration of the bacterium for infection were determined. The suppressive effects of LGG on the adhesion and invasion of Cronobacter in caco-2 ceils were tested by competitive and exclusion experiments, and its inhibitory effect against Cronobacter-induced meningitis was evaluated in neonatal rats. Results Cronobacter showed aggressive adhesion to caco-2 cells with an optimal infection time of 3 h. LGG produced a concentration-dependent inhibition of Cronobacter adhesion and invasion by competing with and excluding the latter for cell adhesion. In neonatal rats, LGG showed an obvious preventive effect and also a moderate therapeutic effect against Cronobacter-induced meningitis. Conclusion LGG can inhibit Cronobacter entry across the intestinal barrier to achieve preventive and therapeutic effects against Cronobacter-induced meningitis.